Field of the Invention
The invention relates to a positioning technique, and particularly relates to a handheld device, an object positioning method and a non-transitory computer-readable recording medium.
Description of Related Art
There are many applications in three-dimensional (3D) scene, for example, virtual reality or refocus of a plurality of objects in a picture, and these applications have been gradually popularized to handheld devices such as smart phones, etc., and these applications all require to detect or calculate positions of a plurality of objects in a 3D space.
A radar can be used to detect a position of an object in the 3D space, though in a radar detection system with a single directional antenna, a relative position of a specific object within an effective irradiation range of the antenna is deduced only according to a radar time of arrival (TOA). If a position of a specific object, for example, a person, a vehicle, a building, etc. in the 3D space is to be obtained, an array antenna has to be used to perform beam scanning. Regardless of an antenna design or back-end operation processing, the above method is hard to be implemented on the handheld devices.
Some high-class handheld devices have two image sensors, which can be used to simulate the human eyes to capture stereo images. These handheld devices can analyze the stereo images by using an image processing algorithm to deduce a general situation of the 3D space. However, in case of a complicated environment, for example, there are too many similar objects in the images, or a too monotonous featureless images are captured, or a characteristic object to be compared in one of the images is shielded due to a viewing angle difference, it is hard to obtain a correct estimation result according to the above method.